January 27th, 2008

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Curvy Women Have Smarter Kids

I just ran across this article. I haven't really checked the science behind it, but what they are saying is that women with broader hips have fat stores of omega 3 fatty acids in their thighs and butts. Belly fat apparently is lower in omega 3's. The brain is built mostly of lipids. This article says that during child development, the brain of the fetus is built from the reserves of omega 3's that the mother has in her thighs. It says that a skinny pregnant woman can supplement omega 3 fatty acids, but that your body prefers to use stored lipids for building baby brains.

http://pmsol3.wordpress.com/2007/11/11/curvy-women-have-smarter-kids/
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Microbiology: Food Poisoning and Anthrax Bacilli

One kind of food poisoning and anthrax are caused by bacterium in the genus Bacillus. They are gram positive rods that make spores and have exotoxins. In lecture there was mention of its marshmallowy capsule containing d-glutamate and that being unusual. The capsule and the exotoxin are plasmid encoded, and this organism is also unique in that it has two plamids.

Bacilli are facultative aerobes--meaning they use oxygen as the final electron acceptor in their electron transport chain, and have catalase and superoxide dismutase. But they can grow in the absence of oxygen by fermenting for energy. The two medically important species of Baccilus are cereus and anthrasis.

B. cereus is ubiquitous in the soil and commonly found in low levels in raw, dried and processed foods. It takes four or more hours in food held at the wrong temperature (warm) to grow enough to make you sick. Beware of steam trays! The food poisoning it causes is similar to that caused by Staphylococcus aureus---watery nonbloody diarrhea 6-18 hours after ingesting the poison, or a faster boot out the top end, or both. Bacillus cereus likes growing in cooked white rice.
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Microbiology: Why Pregnant Women Shouldn't Eat Soft Cheese

There's this lovely bacterium called Listeria monocytogenes that is gram positive and likes to grow in dairy products. It doesn't produce any toxins or spores, it just gets in your cells and kills them. It gets started invading your body via the gut (gastroenteritis), but can take over much more of your body (invasive disease) given enough time. It is one of just a few bacteria that gets inside of your own cells (though this is standard practice for viruses) using a "zipper" mechanism. Once Listeria is inside your cells, the normal macrophage cleanup crew can't find it. It swims inside of host cells by making actin polymers! Listeria can grow at 4 degrees celcius, and is one good reason to we keep meats frozen.

Some 500 deaths/year are caused by Lysteria, and the pregnant woman and baby are most suceptible. The most common way for a pregnant mother to be exposed is by eating soft cheese. The first signs/symptoms of gastroenteritis are watery diarrhea (no blood), fever and headache, myalgias (flu-like). No vomiting. If a 1-4 week old newborn has meningitis, suspect Listeria. It can also get in the placenta during pregnancy and cause sepsis and abortion. Tx for invasive disease: ampicillin.
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